Correlations Between Dispersive Alfvén Wave Activity, Electron Energization, and Ion Outflow in the Inner Magnetosphere

2020 ◽  
Vol 47 (17) ◽  
Author(s):  
A. J. Hull ◽  
C. C. Chaston ◽  
J. W. Bonnell ◽  
P. A. Damiano ◽  
J. R. Wygant ◽  
...  
Keyword(s):  
Wave Activity ◽  
Alfven Wave ◽  
Ion Outflow ◽  
Inner Magnetosphere ◽  
Dispersive Alfvén Wave

Dispersive Alfvén Wave Control of O + Ion Outflow and Energy Densities in the Inner Magnetosphere

2019 ◽  
Vol 46 (15) ◽  
pp. 8597-8606 ◽  
Author(s):  
A. J. Hull ◽  
C. C. Chaston ◽  
J. W. Bonnell ◽  
J. R. Wygant ◽  
C. A. Kletzing ◽  
...  
Keyword(s):  
Alfven Wave ◽  
Ion Outflow ◽  
Inner Magnetosphere ◽  
Dispersive Alfvén Wave ◽  
Wave Control

scholarly journals Wave particle interactions in the high-altitude polar cusp: a Cluster case study

2005 ◽  
Vol 23 (12) ◽  
pp. 3699-3713 ◽  
Author(s):  
B. Grison ◽  
F. Sahraoui ◽  
B. Lavraud ◽  
T. Chust ◽  
N. Cornilleau-Wehrlin ◽  
...  
Keyword(s):  
Electromagnetic Wave ◽  
High Altitude ◽  
Wave Spectrum ◽  
Alfven Waves ◽  
Wave Activity ◽  
Alfven Wave ◽  
Alfvén Waves ◽  
Plasma Convection ◽  
Field Lines ◽  
Kinetic Alfvén Waves

Abstract. On 23 March 2002, the four Cluster spacecraft crossed in close configuration (~100 km separation) the high-altitude (10 RE) cusp region. During a large part of the crossing, the STAFF and EFW instruments have detected strong electromagnetic wave activity at low frequencies, especially when intense field-aligned proton fluxes were detected by the CIS/HIA instrument. In all likelihood, such fluxes correspond to newly-reconnected field lines. A focus on one of these ion injection periods highlights the interaction between waves and protons. The wave activity has been investigated using the k-filtering technique. Experimental dispersion relations have been built in the plasma frame for the two most energetic wave modes. Results show that kinetic Alfvén waves dominate the electromagnetic wave spectrum up to 1 Hz (in the spacecraft frame). Above 0.8 Hz, intense Bernstein waves are also observed. The close simultaneity observed between the wave and particle events is discussed as an evidence for local wave generation. A mechanism based on current instabilities is consistent with the observations of the kinetic Alfvén waves. A weak ion heating along the recently-opened field lines is also suggested from the examination of the ion distribution functions. During an injection event, a large plasma convection motion, indicative of a reconnection site location, is shown to be consistent with the velocity perturbation induced by the large-scale Alfvén wave simultaneously detected.

scholarly journals Solar wind influence on Pc4 and Pc5 ULF wave activity in the inner magnetosphere

2010 ◽  
Vol 115 (A12) ◽  
pp. n/a-n/a ◽  
Author(s):  
W. Liu ◽  
T. E. Sarris ◽  
X. Li ◽  
R. Ergun ◽  
V. Angelopoulos ◽  
...  
Keyword(s):  
Solar Wind ◽  
Wave Activity ◽  
Inner Magnetosphere ◽  
Ulf Wave ◽  
Wind Influence

scholarly journals On the Origin of ULF Magnetic Waves Before the Taiwan Chi-Chi 1999 Earthquake

2021 ◽  
Vol 9 ◽  
Author(s):  
Georgios Anagnostopoulos
Keyword(s):  
Magnetic Field ◽  
Solar Wind ◽  
Interplanetary Space ◽  
Solar Rotation ◽  
Rotation Period ◽  
Wave Activity ◽  
Alfven Wave ◽  
Ulf Waves ◽  
Storm Activity ◽  
Data Set

The ultra low frequency (ULF) electromagnetic (EM) wave activity usually recorded on Earth’s ground has been found to depend on various types of space weather. In addition ULF waves observed before an earthquake have been hypothesized to be a result of geotectonic processes. In this study we elaborate for the first time the origin of sub-ULF (<1 msec) magnetic field waves before an earthquake (Chi-Chi/Taiwan, 20.9.1999) by comparing simultaneously obtained measurements in the interplanetary space (ACE satellite) and on the Earth’s ground (Taiwan). The most striking result of our data analysis, during a period of 7 weeks, is that the detection of four groups of sub-ULF waves in Taiwan coincide in time with the quasi-periodic detection of two solar wind streams by the satellite ACE with approximately the solar rotation period (∼28 days). The high speed solar wind streams (HSSs) in the interplanetary space were accompanied by sub-ULF Alfvén wave activity, quasi-periodic southward IMF and solar wind density perturbations, which are known as triggering agents of magnetic storm activity. The four HSSs were followed by long lasting decreases in the magnetic field in Taiwan. The whole data set examined in this study strongly suggest that the subULF magnetic field waves observed in Taiwan before the Chi-Chi 1999 earthquake is a normal consequence of the incident of HSSs to the magnetosphere. We provide some observational evidence that the sub-ULF electromagnetic radiation on the Earth was most probably a partner to (not a result of) geotectonic processes preparing the Taiwan 1999 earthquake.

scholarly journals Low‐Energy (

2019 ◽  
Vol 124 (1) ◽  
pp. 405-419 ◽  
Author(s):  
Matina Gkioulidou ◽  
S. Ohtani ◽  
A. Y. Ukhorskiy ◽  
D. G. Mitchell ◽  
K. Takahashi ◽  
...  
Keyword(s):  
Low Energy ◽  
Ion Outflow ◽  
Inner Magnetosphere ◽  
Van Allen Probes

Persistent EMIC Wave Activity Across the Nightside Inner Magnetosphere

2020 ◽  
Vol 47 (6) ◽  
Author(s):  
L. W. Blum ◽  
B. Remya ◽  
M. H. Denton ◽  
Q. Schiller
Keyword(s):  
Wave Activity ◽  
Inner Magnetosphere ◽  
Emic Wave

Nonlinear decay of dispersive Alfvén wave and solar coronal heating

2010 ◽  
Vol 77 (2) ◽  
pp. 237-244 ◽  
Author(s):  
SANJAY KUMAR ◽  
R. P. SHARMA
Keyword(s):  
Wave Interaction ◽  
Magnetized Plasma ◽  
Alfven Wave ◽  
Growth Time ◽  
Coupling Coefficients ◽  
Nonlinear Excitation ◽  
Simple Description ◽  
Wave Decay ◽  
Dispersive Alfvén Wave ◽  
Model Equations

AbstractThis paper presents a simple description of three-wave decay interactions involving a pump dispersive Alfvén wave (DAW), decay DAW and decay slow wave (SW) in a uniform magnetized plasma. When the ponderomotive nonlinearities are incorporated in DAW dynamics, the model equations governing the nonlinear excitation of the SWs by DAW in the low-β plasmas (β ≪ me/mi as applicable to solar corona) are given. The expressions for the coupling coefficients of the three-wave interaction have been derived. The growth rate of the instability is also calculated and found that the value of the decay growth time comes out to be of the order of milliseconds at the pump DAW amplitude B0y/B0 = 10−3.

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